Cyclic dinucleotides (CDNs) are ubiquitous small molecule second messengers that regulate a diverse set of processes. Recently, it has been shown that CDNs may have potential applications as therapeutics and/or vaccine adjuvants. For example, certain CDNs have been shown to act as agonists for stimulator of interferon genes (STING), which may inhibit tumor growth and/or boost host antitumor immune response.
However, despite significant research, there remain various challenges which prevent the effective use of CDNs as therapeutics and/or adjuvants. One such challenge includes efficient delivery of CDNs. In particular, poor CDN localization in the cytosolic compartments of tumor associated cells presents a significant barrier to the potential of CDN based cancer immunotherapy.
Accordingly, there remains a need for compositions and methods that provide improved cytosolic drug delivery.